Prospective memory represents the ability of remembering to carry out an intended action in the future. In a typical prospective memory experiment, participants are required to engage in two tasks: the ongoing task and prospective task. According to the nature of the prospective memory cues, there are two types of prospective memory: time-based (TBPM) and event-based prospective memory (EBPM).There are two kinds of processes that can support prospective memory: preparatory attentional processes and memory processes theory (PAM) and multiple processes theory. The PAM assumes that prospective memory retrieval requires resource-demanding preparatory attentional processes, whereas the multiple process theory assumes that retrieval can also occur spontaneously; But according to the regularity of prospective memory, there are also two types of prospective memory: regular prospective memory and irregular prospective memory. Lots of researchers had indicated that regular prospective memory could effectively improve prospective memory results. But those studies did not rule out the possibility of practice effects. Therefore, in the case of the possibility of practice effects, we explored the effect and mechanism of regular prospective memory. Some researchers argued that the knowability of execution situation may affect prospective memory. Therefore, we separated regular prospective memory into two conditions: one was that we knew the regularities, the other was the complete opposite. Our aim was to detailedly and deeply explore the effect and mechanism of regular prospective memory. In addition, we employed a new eyetracking paradigm to concretely investigate the impact of regular environmental cues within a visual prospective memory task. Experiments were programmed by Experiment Bulider. The present study adopted a single factor design. A total of 53 college students (18 no regularity, 17 unknown regularity, 18 known regularity) participated the experiment. Participants were asked to respond by pressing the key (A or B), but when meeting the prospective memory cues they should press the specified key (C). The hypothesis was that both accuracy and reaction speed of regular prospective memory (including unknown regularity and known regularity) were better than irregular prospective memory. During the course of experiments, Ongoing task and PM task were done simultaneously by participants. Participants’ behavioral data and eye-movement data were recorded by computer automatically. The results showed that both accuracy and reaction speed of regular prospective memory were better than irregular prospective when the execution situation was known. But there were no difference when the regular situation was unknown. The eye-movement data showed that participants tend to pay more attention to prospective memory cues and regular situation when regular situation was known. The main stream theories could not explain the results. But cognitive resources limitation model argue that cognitive resources were limited. According to situation, participants could allocate the cognitive resources in a flexible style. When the regular situation was known, participants could make a plan in the light of whether the regular situation would appear. When regular cues were not presented, they did not allocate much more cognitive resources to prospective memory tasks. However, when regular situation was coming, they would pay more attrition to prospective memory cues.